Hoya 49mm Dual Color Red/Blue Special Effects Glass Filter
Available in three types: O/G (Orange/Green), Y/P (Yellow/Purple) and R/B (Red/Blue).
Made by sandwiching gelatin filters between two pieces of optical glass, DUAL-COLOR is available in a variety of two-color combinations.
Contrasting foreground and background, land and sea, are only a few of the fantastic possibilities. The mount is turnable allowing you the freedom to vary the effect to your liking.